1. Field of the Invention
The present invention relates to a liquid crystal display device in which liquid crystal molecules are aligned by an electric field generated by two electrodes stacked via an insulating layer.
2. Description of the Related Art
Conventionally, liquid crystal display devices are classified into ones of a vertical electric field system and ones of a horizontal electric field system. A liquid crystal display device of the horizontal electric field system may obtain wider viewing angle characteristics compared with those of a liquid crystal display device of the vertical electric field system. Among liquid crystal display devices of the horizontal electric field system, ones in which a pixel electrode and a common electrode are stacked via an insulating layer, one of the electrodes having slits formed therein and the other of the electrodes being in the shape of an even plane without an opening, are used when high transmittance is required. This is because an arc-like electric flux is distributed to the vicinity of the center of the electrode having the slits formed therein so as to connect the pixel electrode and the common electrode which are in different layers.
By the way, examples of the electrode having slits formed therein include a comb electrode in which one ends of the slits are closed while the other ends are open, and an electrode in which both the ends of the slits are closed. Further, in a multi-domain liquid crystal display device, such slits in the electrode are inflected. When an electric field is generated by an electrode having slits formed therein and an electrode in the shape of an even plane without an opening, an electric field in the vicinity of ends in a longitudinal direction of the slits or in the vicinity of inflected portions of the slits is distributed in such a way that control of the alignment of the liquid crystal molecules is difficult. Therefore, a region in which the alignment of the liquid crystal molecules cannot be controlled (hereinafter, referred to as domain) is generated in the vicinity of the ends in the longitudinal direction of the slits or in the vicinity of the inflected portions of the slits. The domain is responsible for lowering the transmittance in the liquid crystal display device. Accordingly, as disclosed in, for example, Japanese Patent Application Laid-open No. 2008-276172, a liquid crystal display device which reduces such a domain has been proposed.